Occlusal Ordered Membrane Electrode Assembly (MEA) with Conformal Array Structure and Superior Performance by Constructing Nested Interface

Abstract The ordered structural design improves the protons, electrons, and mass transport in proton exchange membrane water electrolysis (PEMWE), increases the electrochemical active surface area (ECSA) as well as catalyst utilization. However, the advantages of the array structure in conventional ordered membrane electrode assembly (MEA) could not be fully exploited due to the extrusion and disruption of the array structure by the porous transport layer (PTL). Herein, an occlusal ordered MEA with conformal array structure based on the laser‐perforated PTL is proposed and ordered catalyst‐coated membrane (CCM). Compared with conventional ordered MEA, it greatly improves the interfacial contact between CCM and PTL due to effectively protecting the array structure. As a result, the occlusal MEA not only greatly increases the ECSA by 2.69 times but also decreases the ohmic resistance and charge transfer resistance by 22.3% and 41.9%, respectively, compared with conventional flat MEA. It achieves a superior performance with a current density of 10.78 A cm −2 , 2.1 times higher than that of the conventional flat MEA at 80 °C and 2.0 V. This work provides a new strategy for the structural design of ordered MEA.